Sierra Club sues Exxon over Baytown plant pollution

(Reuters) - The Sierra Club and Environment Texas filed a federal lawsuit against Exxon Mobil Corp for five years of excess pollution at the nation's largest refinery, the Sierra Club said on Tuesday.

The two groups over three years have won settlements with Shell Oil Co and Chevron Phillips Chemical Co for pollution at Houston-area refineries and chemical plants.

Tuesday's lawsuit alleges Exxon's 560,540 barrel per day refinery and chemical plant in Baytown, Texas, committed over 2,500 violations of the U.S. Clean Air Act between 2005 and 2010, releasing over 8 million lbs of pollutants, said Neil Carman, clean air director of the Sierra Club's Texas chapter.

If successful, the lawsuit could cost Exxon $81.25 million in fines, according to the Sierra Club.

In settling its lawsuit, Shell agreed to specific pollution limits at its Houston-area refinery and chemical plant complex and set fines if it failed to comply with the limits.

"We're seeking for Exxon to clean up the Exxon Baytown refinery," Carman said on Tuesday morning. "They need to comply with the law."

An Exxon spokesman said the company would oppose the Sierra Club lawsuit.

"Over the last five years, the Baytown refinery and chemical plant, one of the nation's largest and most complex petrochemical facilities, has produced total annual emissions that are nearly 40 percent below the federal permit limits set by (the U.S. Environmental Protection Agency)," said Exxon spokesman Kevin Allexon in a statement.

The Sierra Club and Environment Texas based their number of violations on reports of excess pollution filed by the Baytown refinery and chemical plant with state and federal pollution regulators, as required by law.

Among the pollutants released by the Baytown refining and chemical plant complex are benzene, hydrogen chloride, hydrogen sulfide, sulfur dioxide and nitrogen oxide, Carman said.

Allexon said Exxon has invested nearly $1.3 billion to reduce pollution sourced from the Baytown complex.

"Since 2001, there has been an 89 percent reduction in upset/maintenance emissions, a 58 percent reduction in total emissions (routine and upset), and a 62 percent reduction in the number of reportable air incidents," Allexon said.

The emissions reported by the Baytown complex are six times those released by the BP Plc's Texas City, Texas, refining and chemical complex, which is being sued by the Texas Attorney General's office for excess pollution, Carman said.

U.S. refineries operate under permits that license the facilities to release a set amount of pollution in daily, weekly and annual periods. When a refinery exceeds those limits, it must notify state and federal regulators.